A joint research program is proposed involving the chemical synthesis of stereoregular polysaccharides and oligosaccharides, their modification for use as haptens and antigens, their separation, as may be neccessary, into specific molecular weight fractions, coupling to proteins by standard methods, testing for immunogenicity and cross- reactivity in mice and other animals. It will be possible to investigate in this fashion, alpha-(1 yields 6)-linked stereoregular polysaccharides consisting of D-galactose in copolymers only and D- glucose and D-mannose in homopolymers and in copolymers of predictable monomer sequence lengths. In at least some cases it will be possible to prepare di-, tri-, and tetra- (homo and hetero) saccharides of the same linkages coupled to protein for use as antigens and investigate them as antigenic determinants for the corresponding polysaccharides, and to determine minimal molecular requirements. As more complex di-, tri- and tetrasaccharides of galactose, glucose, mannose and fucose can be synthesized, they will be used similarly in immunization. Formation of specific antibodies will be tested by passive cutaneous anaphylaxis and the hyperimmune antisera will be tested for their ability to attach to cell surfaces in suitable test tissues. Fluorescent markers will be used to visualize antibodies attached to cells or tissues. As methods are developed for the synthesis of beta-(1 yields 4), (1 yields 6), and (1 yields 2)-galactans, these will be synthesized for testing the specificity of homogeneous immunoglobulins from plasmacytomas in mice. Binding constants will be measured by quantitative alteration of tryptophane fluorescence upon ligand binding to immunoglobulin.